Power generating system



Jan. 5,- 1943. M; H, ELK. 2,307,365

POWER GENERATING SYSTEM Filed June 27, 1941 INVENTOK 6M A f-wwstarting switch end of which is normally grounded through con- Patented Jan. 5, 1943 UNITED STATES PATENT OFFICE 2,307,365 POWER- GENERATING SYSTEM Manuel H. Elkin,

Elmira Heights, N. Y., assignor to Bendix Aviation Corporation, South Bend Ind, a corporation of Delaware Application June 27, 1941, Serial No. 400,053

7 Claims.

The present invention relates to a power generating system and more particularly to an automatic system of the type in which closure of a load switch causes the power system to come into operation and to continue to operate as long as there is any load on the supply line.

It is an object of the present invention to provide a novel generating system which is simple in construction, reliable in operation and completely automatic in respect to all normal conditions of operation,

It is another object to provide such a system which is readily adapted to incorporate existing commercial devices for performing the various automatic starter control operations.

Further objects and advantages will be apparent from the following description taken in connection with the accompanying drawing which shows semi-diagrammatically a power generating system incorporating a preferred embodiment of the invention.

In the drawing there is illustrated a prime mover in the form of an internal combustion engine I having a conventional form of 'magneto-electric ignition system indicated generally by numeral 2 and controlled by a pair of contacts 3, closure of which grounds the magneto and thus renders the ignition system inoperative.

A service generator 4 is adapted to be driven by the engine I in any suitable manner as by means of a belt 5, and is adapted to supply power at service voltage such as 110 volts to a load circuit comprising a hot lead 6 and a grounded lead 1. The generator 4 may be of the direct current type or the alternating current type as may be preferred. The load elements to be supplied with power are connected across the leads 6 and l with individual switches for turning said elements on or off. One such load element is illustrated in the form of a lamp 8 connected across the supply line and controlled by means of a switch 9.

A starting circuit for the engine I is provided comprising a battery II of a suitable low voltage such as 6 or 12 volts, connected at I2 to the grounded lead 1 of the supply line and connected by a lead I3 to an automatic starter controlling device indicated generally by numeral I4. Since this controlling device is a well-known commercial product and is described, for instance, in the patent to Loehr and Burdick, No. ur-

ther description thereof is deemed unnecessary except to state that it comprises a magnetic I4I actuated by a coil I42, one

tacts I43 which are opened by an arm I44 actuated by a solenoid I46. When its control circuit is closed, the engine will be automatically cranked, and cranking will be interrupted when the engine starts. The starting circuit is completed by a lead I5 through the starting motor SM and lead I 6 to the ground.

Means for maintaining the battery I I in properly charged condition is provided in the form of a direct current generator G of suitable low voltage which is driven from the engine I in any suitable manner and has one terminal I1 grounded at I8 while its other terminal I9 is connected to the battery through an automatic cutout 2I and lead 22.

According to the present invention means are provided whereby closure of a load switch such as the switch 9 will cause the engine I to be placed in operative condition, the starting mechanism actuated, and the engine maintained in operation as long as there is any demand for current in the supply system. As here illustrated this is accomplished by means of three relays 23, 24 and 25. Relay 23 is adapted to be actuated by battery voltage to close a starter control circuit when there is a demand for power in the load circuit. Relay 24 has its contacts in shunt with the contacts of relay 23 and is designed to be closed by the load current when the service generator 4 is operative to supply current to such load. The starter control circuit is thus maintained closed as long as a current flows in the load circuit. Relay 25 is actuated by the voltage of the service generator 4 to disconnect the load circuit from the battery I I and connect it to the service generator 4, when the engine rotates the generator at sufiicient speed to render it operative. For this purpose the coil 25I of relay 25 is connected directly across the out-put of said generator by means of leads 252 and 253.

The starter control circuit comprises a lead 26 connected to the battery I I, lead 21, contacts 28 of relay 23, lead 29 and a thermostatic crank- .ing time limiter indicated generally by numeral 45.

to Elkin, No. 2,202,550, and forms no part of the present invention. The cranking time limiter is connected by a lead 32 to a backfire circuit breaker 33 of the type described in the patent to Christian, No. 1,986,673, which in turn is connected by a lead 34 to the coil I42 of starter control device I4.

In order to cause closure of contacts 28 of relay 23 to close the starter control circuit when the load switch 9 is closed, the coil 35 of the relay 23 is connected at one end to the battery lead 26 and at the other end is connected by a lead 35 to the contact 3? of relay 25. Contact 38 of said relay is onnected by lead 39 to one end of coil M of relay 2%, the opposite end of which is connected to the lead ii of the load circuit.

gization of said electro-magnet, opening contacts 3 and breaking the grounding circuit of the ignition magneto.

In operation, starting with the parts in the positions illustrated, closure of the load switch 9 completes a circuit through the battery Ii, lead 26, coil of relay 23,1ead 36, contacts 31, 42 and 33 of relay 2%, lead 33, coil ll of relay 24, lead of the load circuit, load device 8, switch 9 and grounded lead '1 back to the battery through connection H2. The consequent energ'ization of the coil 35 causes closure of contacts 28 of the relay 23. This completes the starter control circuit from battery i I through the leads 26 and 27, contacts 23, lead 29, cranking time limiter 35, lead 32, backfire circuit controller 33 and lead 3Z3 to the coil M2 of the automatic starter control device it. The consequent energization of coil M2 causes the magnetic starting switch It! to close, which completes the starting circuit from battery I! through leads l3 and I5 to starting motor SM, whereby the engine is cranked. At the same time the energization of the electro-magnet at from the control circuit lead 34 by means of lead (it causes the engine ignition to be rendered operative.

When the engine starts and the service generator 5 is brought up to operative speed, the consequent voltage across the coil 25! of relay 25 causes the bridging contact at to disconnect contacts 31' and connect contact 48 to contact 38. The battery H is thus disconnected from the load circuit, and the service generator voltage is applied to said circuit through lead 252 to energize the load device 8. When the engine becomes reliably self-operative, the low voltage generator G energizes the look-out coil I46 of'' the starter controlling device Hi through leads 66 and il whereby contacts H43 are held open and the cranking circuit thus maintained dee'nergized. I Y

If desired, the action of the generator G on the lead 50 in order to prevent the battery from discharging through the generator during the cranking operation.

Although but one form of the invention has been shown and described in detail, it will be understood that other embodiments are possible and various changes may be made in the design and arrangement of the parts without departing from the spirit of the invention as defined in the claims appended hereto.

What is claimed is:

1. In an electrical power generator system an internal combustion engine, a starting system therefor, including a battery, a service generator driven by the engine, a load circuit fed by the generator, means connecting said battery to the load circuit when the generating system is not in operation, means responsive to closure of the load circuit for actuating the starting system, means responsive to self-operation of the engine for deenergizing the starting system and maintaining it deenergized as long as the engine remains self-operative, and means responsive to rotation of the engine at substantially its normal operating speed for disconnecting the load circuit I from the battery and connecting said circuit to shown in the patent to Maurer, No. 2,071,042. As

here shown this is accomplished by connecting one terminal 23 of a vacuum diaphragm control unit 49 to the control circuit lead 29 by means of a lead 5i} and by connecting the other terminal 5! of the diaphragm control by a lead 52' to the generator lead it. The contacts of the dia- 'phragm control iQ are normally open but are closed by intake vacuum whereby the lock-out circuit is completed through the battery to the coil hit when there is a vacuum in the engine intake. A resistor 53 is preferably inserted in the service generator.

2. In an electrical power generating system, an internal combustion engine, a starting system therefor, including a low voltage battery and a starting motor, a control circuit for the starting system, a load circuit, a service voltage generator driven by the engine for supplying the load circuit, switch means connecting the battery to the load circuit when the generating system is idle, a relay for closing the starter control circuit having its coil connected in series between said switch means and the battery, means responsive to voltage of the service generator for actuating the switch means to disconnect the battery from the load circuit and connect the service generator to said circuit, and a relay in shunt with the control circuit relay having its coil connected in series in the load circuit.

3. In an electrical power generating system an internal combustion engine, a service generator connected to be driven thereby, a starting system for the engine including a battery, a power distributing circuit to be fed by the service generator, a magnetic switch adapted when deenergized to connect the battery to the distributing circuit, and when energized by voltage of the service generator to connect said generator to the distributing circuit, a starting control circuit, and a pair of magnetic switches in parallel for closing said control circuit, one magnetic switch being adapted to be energized by low voltage current flowing through the circuit when the battery is connected thereto, and the other magnetic switch being energized by load current when the generator is connected to the distributing circuit.

4. In a two-voltage electrical power generating system an internal combustion engine, a service generator and a low voltage generator driven by said engine, a power distributing circuit, a start- :ing system for the engine, a control circuit for the starting system including two magnetic switches in parallel, one being adapted to be closed by low voltage current from the battery and the other being adapted to be closed by load current, and a magnetic switch energized by voltage of the service generator to connect the service generator to 'the power distributing circuit.

engine having an ignition system, an alternating current generator driven thereby, a power supply circuit, a starting system for the internal combustion engine including a battery, a control circuit for the starting system including the battery and an electro-magnetic relay, and a demand circuit for controlling the relay including the supply circuit, whereby closure of the supply circuit causes closure of the relay and consequent initiation of the starting operation and an 10 alternating current relay energized by the generator for disconnecting the supply circuit from the demand circuit and connecting the supply circuit to the generator.

6. An electrical power supply system as set forth in claim 5 in which said supply circuit includes an alternating current relay maintaining the ignition system of the internal combustion engine operative as long as the supply circuit is closed.

7. An electrical power supply system as set forth in claim 5 in which said starter control circuit includes a direct current relay for rendering the ignition system of the internal combustion engine operative during the starting operation.

MANUEL H. ELKIN. 

